1. Field of the Invention
The present invention relates to an ink jet recording apparatus and, more particularly, to an ink jet recording apparatus capable of preventing light from a light source from entering into a recording head.
2. Description of the Related Art
Recently, for performing image recording on a packing material, there have been generally used a gravure printing method and a flexographic printing method. However, a plate making process is required for the gravure printing method and a flexographic printing method, so that they are disadvantageous in small-lot printing in view of the cost.
As an image recording method capable of easily recording images at low cost, there is known an image recording apparatus in which ink jet system is used (hereinafter, referred to as “ink jet recording apparatus”). The ink jet recording apparatus comprises a recording head for jetting ultraviolet curable ink onto a recording medium as droplets, and a light source for radiating light to cure the ink jetted onto the recording medium. A carriage on which the recording head and the light source are mounted is moved over the recording medium to perform image recording (for example, see JP-Tokukai-2001-310454A).
However, in such the ink jet recording apparatus, when continuously performing image recording, the ink which is jetted from jet openings of the recording head turn into spray would cause clogging, that is, the ink would adhere and deposit at a portion near the jet openings of the recording head, and clog in the jet openings. Continuing image recording in this condition would cause problems such as a failure of jetting ink.
Therefore, a recent ink jet recording apparatus is provided with a maintenance unit so that the recording head can be recovered from clogging to normally perform image recording by removing ink adhered to the jet openings of the recording head and a portion near the jet openings.
The above described ink removing operation is performed by moving a carriage on which the recording head is mounted to a maintenance region where the maintenance unit is arranged.
The maintenance unit comprises a suction cap member to suction and remove ink clogged in the jet openings of the recording head, and a wipe member to wipe ink adhered and deposited at the jet openings and a portion near the jet openings. The suction cap member covers a nozzle-plate of the recording head to suction the ink, and the wipe member wipes the nozzle-plate by a blade.
However, the above maintenance unit arranged in an exposed state would be directly irradiated with light radiated from a light source in a maintenance operation. Thus, the light radiated from the light source would be diffusely reflected from a surface of the maintenance unit on the recording head side, thereby entering into a portion near the jet openings of the recording head.
Therefore, since photo curable ink adhered to the jet openings and a portion near the jet openings is cured, problems arise, such as a failure to jet ink, that is clogging, or a failure to jet ink droplets in a correct direction, that is ink jet path bending.
Moreover, photo curable ink adhered to and cured on the suction cap of the maintenance unit or the wipe member would result in a failure to normally perform maintenance.